1. Field of the Invention
The present invention relates to a display device comprising a light-emitting element, a driving method thereof, and a television set.
In addition, the invention relates to an electronic apparatus provided with the display device comprising a light-emitting element.
2. Description of the Related Art
In recent years, a display device comprising a light-emitting element typified by an EL (Electro Luminescence) element has been developed, which is expected to be widely used taking advantage of the self-luminous type such as high image quality, wide viewing angle, thin type, and light weight.
There is an application having an object to solve a problem of lack of luminance and the like, which is due to decrease in the duty ratio (the ratio of a light-emitting period to a period including the light-emitting period and a non light-emitting period), by employing novel driving method and circuit in the display device comprising a light-emitting element (see Patent Document 1). According to Patent Document 1, a signal is written to pixels at a plurality of rows within one gate signal line selecting period. Therefore, in pixels at any row, a period from a signal is inputted until a next signal is inputted can be set arbitrarily to some extent with a sufficient writing period to the pixels, so that a sustain (light-emitting) period is arbitrarily set and the high duty ratio is realized. In addition, there is an application to provide a method for performing multi-gray scale display of an electro-optic device by a time gray scale method without providing a reset line (see Patent Document 2).    [Patent Document 1] Japanese Patent Laid-Open No. 2001-324958    [Patent Document 2] Japanese Patent Laid-Open No. 2002-175047
When employing the driving methods described in Patent Documents 1 and 2, a display defect which is called a ghost may occur. The ghost is such a phenomenon that when an image (here a white box) is displayed in the middle of a display screen for example, the same image is also displayed in the above and below (see FIG. 15). The display defect which is called a ghost is caused by an overlap period (denoted by Tk in the drawing) between a period for outputting a video signal to a pixel by a source driver and a period for selecting a gate line (here the i-th row gate line) by an erasing second gate driver occurs so that video signal is written to a pixel where an erasing operation is performed (see FIG. 16).